A new 50-nm nMOSFET with side-gates for virtual source-drain extensions

We have proposed and fabricated a novel 50-nm nMOSFET with side-gates, which induce inversion layers for virtual source/drain extensions (SDE). The 50-nm nMOSFETs show excellent suppression of the short channel effect and reasonable current drivability [subthreshold swing of 86 mV/decade, drain-induced barrier lowering (DIBL) of 112 mV, and maximum transconductance (g_m) of 470 μS/μm at V_D=1.5 V], resulting from the ultra-shallow virtual SDE junction. Since both the main gate and the side-gate give good cut-off characteristics, a possible advantage of this structure in an application to multi-input NAND gates was investigated.